JavaScript is disabled
Our website requires JavaScript to function properly. For a better experience, please enable JavaScript in your browser settings before proceeding.
Messages
14,308
Reactions
24,934
...well kinda....
If your not a reloader, the caveat to this is you have to buy a press and a seating die but don't worry your still not reloading anything.... continue.

So anyways I was watching another Eric Cortina video taking notes when he discussed a side topic about factory ammo. Basically most people keep trying different brands until you find the one that shoots the best, is essentially finding the one with a seating depth node that matches your barrel. He then went on to explain that, lets say you found the "best" but it still isn't good enough... you could, tune the ammo by adjusting its seating depth from where it is. (22:20 mark)
Ask for how and why in the comments if needed.

Part2 for the handloaders. (19:06 mark)
Another thing that stood out to me was when he said "seating depth will tune any load".
Every loads group size can be tuned by adjusting seating depth. If it doesn't shrink enough, change your combustion components, but it can be shrunk to some extent. This was an epiphany to me because it applies regardless of distance to lands, such as a magazine restricting COAL. I always assumed if I couldn't get good group size it was because I couldn't load closer to the lands if I had a magazine limitation. I have a new trick to try.

View: https://youtu.be/9FKq8Jj8YEI?si=C64Wu4eLtL8cdPxk&t=1146
 
Bullet seating depth CAN make a difference but it's generally considered the fine tune step after powder, powder charge and other things have been optimized.
 
Bullet seating depth CAN make a difference but it's generally considered the fine tune step after powder, powder charge and other things have been optimized.
Agree, he did mention that but I was paraphrasing.
One thing he didnt point out very clear was what if the load is just at its best seating depth node by coicedence, you cant really adjust it. If its a factory round you cant change combustion components and I wouldnt want to keep seating things deeper and deeper looking for a new node. He didnt really mention a limit to it and at some point it can be a safety issue.
 
I've messed with seating depth twice. The 222 rem "seemed" to work (below), but my 30-06 and copper boolots has no hope.

7-22-24   222.jpg
 
One of the reasons this was an epiphany to me is because for a long while I wasn't using seating depth to tune my loads with the bullets I use, (from wrong reasons). I was getting 1.5moa groups with my 280ai and frustrated it wasn't smaller but usable for hunting. Finally convinced to try a seating depth test I got it down to .8moa average group size and was thrilled to finally be under my 1moa max goal. I could literally see the group size shrinking on the test target like a textbook example, I was thrilled.
Excited about this new revelation I went to develop a new handload for my 25-06ai only this time I started .020" off the lands and the best group with the OCW test was .3moa so I didn't need to play with seating depth testing, fasted handload Ive worked up yet.

But I look forward to revisiting this subject with my AR handload which is greatly restricted by magazine length but that will be a while, its hunting season in 2 days. When I watched this video tonight for the first time it all added up and confirmed a lot of my thoughts on if I could use this to tune my AR handload but distance to the lands doesnt matter. The video also seems to support the idea there are multiple seating depth nodes to any load.
 
So many people talk about loading to "touch the lands" or even "ten thou into the lands". I have always found that jump gives me better accuracy, and me playing with a node involves making it jump more.
With the last barrel (3rd one) I had cut for my 6.5 Swede AI, I gave the gunsmith a bullet with exaggerated seating depth (loading long), which in turn gives me a longer leade. When I'm through with my 2nd barrel, I think I'll have fun playing with loads.
 
So many people talk about loading to "touch the lands" or even "ten thou into the lands". I have always found that jump gives me better accuracy, and me playing with a node involves making it jump more.
With the last barrel (3rd one) I had cut for my 6.5 Swede AI, I gave the gunsmith a bullet with exaggerated seating depth (loading long), which in turn gives me a longer leade. When I'm through with my 2nd barrel, I think I'll have fun playing with loads.
Oh a long throated improved 6.5 is going to give up some impressive ballistics...

One of the learning roadblocks for me was what seating depth to begin load development should be. Ask and you get unlimited answers but no reason to why. It technically might not matter regarding seating depth nodes (barrel harmonic nodes) but eventually I realized closer to the lands allows more case volume (more velocity, less pressure) so I start now at .020". I don't want to be close to the lands in case I misread my calipers or something.
 

Upcoming Events

Centralia Gun Show
  • Centralia, WA
Falcon Gun Show
  • Granite Falls, WA

New Classified Ads

Back Top